Biological control of Australian acacias

John Hoffman- University of Cape Town

Biological control is being used against 13 species of invasive Australian acacias in South Africa with agents compromising two gall midges (Cecidomyiidae), two gall wasps( Pteromalidae), several seed beetles (Curculionidae) and a rust fungus (Basidiomycetes).

The fungus is the only agent that damages the whole plant. The insects are all associated with the flowers and seeds on the plants.

It is 40 years since the first agent was released, the bud gall wasp Trichilogaster acaciaelongifoliae on Long-leaved wattle (Acacia longifolia).